| 摘要 |
PROBLEM TO BE SOLVED: To reduce the passing loss by forming a conductor thin film with a cavity corresponding to the location of a microstrip on the rear side of a microstrip dielectric board and fixing a ground metallic conductor to the conductor thin film. SOLUTION: A part of a rear conductor thin film 5 formed in advance by vapor-deposition or the like on the rear side of a dielectric board 2 where a microstrip 1 is placed on the front and corresponding to the microstrip 1 is exfoliated or removed in advance in the case of forming a pattern of the board. Thus, in the case of soldering or screw-fastening the dielectric board 2 and a ground metallic conductor 4, a cavity layer 3 is formed between the dielectric board 2 and the round metallic conductor 4 corresponding to the board 2. Through the constitution above, even when a dielectric board whose dielectric constant is high is in use, since the dielectric constant of the cavity layer is '1', the combined dielectric constant is nearly '1', the wavelength reduction rate of the circuit is increased, and a transmission loss of the microstrip line is as small as that formed on a dielectric board whose dielectric is nearly '1'. |
